Sorry to spam you with so many tiny details: I am running through the game testing industrialization strategies, and this allows me to zip through 5 years relatively quickly. As I have seen unexpected event results in later years (that I normally never get to in battle mode), I thought I would share them for your evaluation.
In 1862, the Sioux rise in the Great Plains. The Union event directs me to keep 3 units there until 1863, or lose VP. (Ironically the VP loss is minor.) Having failed it a couple of times, I decided to park some units there in advance, as my clairvoyant strategy.
It still fails every time: -25 VP lost in September 1862. Don't know why. Doesn't seem to matter if I destroy the indians or not.
Is it possible the minus sign is reversed?
All the Best, -D